Can I established glide slope before Intermediate Approach Fix
 

I have this question when I fly in China. Some times, like one day, I fly on the left downwind of runway 05 in Xiamen (ZSAM) airport for the ILS/DME approach. The altitude at FAF is 2300ft, because of military activity, the tower let me extended downwind and maintain 3900ft. We fly 3NM more after abeam the IF (Intermediate Approach Fix) and then got the clearance to turn to final. At the same times the tower said 'clear ILS/DME approach runway 05'. So after we established the LOC, the G/S almost on the right path,but we are not reach the IF yet. My first officer said that we can establish the G/S and shoot the approach, but I think maybe we'd better us vertical speed to descent and maintain the G/S until we passing the IF. He give me the reasons like that we under the Radar and higher then every minimums, I agree with these but I still think that is not comfortable for me.
So dear controllers, could you give me your opinions whatever under FAR,JAR or some else. Thanks a lot!

Ryan

Once you get an approach clearance you can follow the approach all the way to the ground.

A point to consider is that the glideslope is only protected from 13 miles (localiser similarly to 17 nms) according to the general notes in Jeppesen.

you need to hit faf at said altitude...so need to descend..me thinks

thanks all

The best thing is always to ask

On some approaches (e.g. LAX, but maybe not in China) fix minima prior to the FAF may be above the GS, so following the GS outside the FAF may be unsafe.

Before the FAF you should refer to minimums from other sources than glide slope like MSA or initial approach altitude. If radar is vectoring you or has given you a direct routing the obstacle clearance is his/her responsibility. It is a good practice from atc to give you the altitude that you can descent to. If you are not sure, ask.

I am happy with that part. Personally I like to find the G/S far out and just follow it down as reference for a continuous descent. I do of course confirm that the G/S doesn't take me below any "hard altitude", issued descent clearance, step-down altitude etc. The G/S is normally only protected to a certain distance, 10 nm in US. For the most part you can pick it up earlier than that. And once again, as long as I don't bust any altitude limits it's a good reference.